Close to starting, pops out exhaust

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beast02
MegaSquirt Newbie
Posts: 22
Joined: Mon Jan 30, 2006 12:35 pm

Close to starting, pops out exhaust

Post by beast02 »

Well, i'm finally close to getting the car started, but I'm right at the point where it backfires/pops out the exhaust after about 5-8 seconds of cranking. So, something with the ignition seems to be off a bit, though I'm having trouble figuring out what. I am posting 2 small datalogs to see if anyone can see something I don't.

Checked the plug wires, looking in to the plug wire plugs at the coil with the terminal facing down, order I have is 1 and 4 on the left and 3 and 2 on the right (firing order of car is 1342)

Details are MSII V3.0
EDIS-4
running 2.687 code

I am so close, I hope it is something simple and stupid!

Thanks
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a73camaro

Re: Close to starting, pops out exhaust

Post by a73camaro »

Try swapping the spark plug wires between the two coils. It sounds like you are a 180º out.
convertables_10
Helpful Squirter
Posts: 104
Joined: Wed Jul 21, 2010 9:18 am

Re: Close to starting, pops out exhaust

Post by convertables_10 »

Sounds like its 180* out of time. You can swap your wires around on the coil and if its 180 out itll fire.
My MegaSquirt build 85 S-15 Jimmy 350/th350 TPI MS2 2.905 hei 8pin
1983 s-10 350 tpi injection MS2 soon
1984 s-10 Blazer 350/th350 and will get an MS2 tbi.
1973 Nova 5.3/glide 76mm turbo. MS3X
beast02
MegaSquirt Newbie
Posts: 22
Joined: Mon Jan 30, 2006 12:35 pm

Re: Close to starting, pops out exhaust

Post by beast02 »

I am hoping you guys are right! Plug wires are in the same spot as when I had the car running with carbs on (i tested the EDIS in limp home before I pulled and did the full EFI), so I guess this 180 out could only be the case if I mixed up the two wires for the coil A/B sides eh?

Is there no settings in megatune that I could have wrong that would cause this? I configured per the EDIS portion of the manual, though there are a few settings at the top of the box that the manual doesn't really cover that I have not changed.

I'll test the wires tonight

-Bryan
beast02
MegaSquirt Newbie
Posts: 22
Joined: Mon Jan 30, 2006 12:35 pm

Re: Close to starting, pops out exhaust

Post by beast02 »

Yes, this was the issue. I have to adjust my mindset......I thought it could be this....but then I just assumed since I had hooked it up the way I did last time (or assumed I did) that it had to be a setting.

Thanks for pointing out what was probably obvious! It starts!! now the tricky part begins!
convertables_10
Helpful Squirter
Posts: 104
Joined: Wed Jul 21, 2010 9:18 am

Re: Close to starting, pops out exhaust

Post by convertables_10 »

Ive installed a distributor 180 out a time or 2. Glad it fixxed your issues.
My MegaSquirt build 85 S-15 Jimmy 350/th350 TPI MS2 2.905 hei 8pin
1983 s-10 350 tpi injection MS2 soon
1984 s-10 Blazer 350/th350 and will get an MS2 tbi.
1973 Nova 5.3/glide 76mm turbo. MS3X
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